SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2020-37280

cbor-sync through 1.0.4 contains a resource exhaustion vulnerability in CBOR.decode that trusts declared array and map lengths without checking remaining input.

HIGH 8.7EPSS 0.54%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.54%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

cbor-sync through 1.0.4 contains a resource exhaustion vulnerability in CBOR.decode that trusts declared array and map lengths without checking remaining input. Remote attackers can supply a tiny crafted CBOR payload declaring huge lengths to drive billions of iterations, exhausting CPU and process memory.

CVSS 4.0
8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.54% probability · 45th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-789
Source
disclosure@vulncheck.com
EPSS trend
0%3%5%13 October 2026: 0.54%26 October 2026: 0.54%13 October 202626 October 2026

EPSS moved from 0.5% on 13 October 2026 to 0.5% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.